Length-grading mechanism for copying lathes



S. E. BO YNTON.

LENGTH GRADING MECHANISM FOR COPYING LATHES.

' APPLICATION man 'Nov. 24. 1920.

1,402,? 3'7 Patented Jan. 10, 1922,

a-sHlEETs-sHEH 1.-

INVENTUR S.E.BOYNION. LENGTH GRADING MECHANISM FOR COPYING LATHES,

I APPLICATION FILED NOV. 24,1920. I 1,402,737. I Patented Jan. 10, 1922,

v 3 SHEETS-SHEET 2.

",UNETEQ fiTATEfi EATENT Qf'FlQE.

STANLEY E. BOYNTON, OF ROCHESTER,

NEW Yon-K, AssIGnon o FITZ-EMPIRE DOUBLE PIVOT LAST COMPANY, (3F AUBURN, MAINE, A CORPORATION OF MAINE.

LENGTH-GRADING MECHANISDI FOR COPYING- LATHES.

Application filed November 2 1, 1920. Serial No. 426,125.

T 0 all whom it may concern:

Be 1t known that l, STANLEY E. Born- TON, acitizen of the United States, and residing at Rochester, in the county of'Monroe and State of New York. have invented certain Improvements in Length-(trading Mechanisms for Copying Lathes, of which the following description, in connection with the accompanying drawings, is a specification, like reference characters on the drawingsindicating like parts in the several figures.

This invention relates to grading mechanisms used in machines for producing articles having a systematic resemblance to a pattern and is herein disclosed as embodied in a last lathe. It should be understood, however, that the invention, especially in some aspects, is not limited to this particular type of copying machines, or indeed, to machinesfor producing solid objects It is customary in making a set or run of lasts to grade them 1}; inch per size in length, regardless of style. That is, the will always be inch longer than the #4: model, while the absolute length of the #4 will depend 011 the style of toe. The magnification factor necessary to extend the #4 by inch will therefore vary with the style. The mens model is a #7 instead of a so that the variations in the magnification factor necessary to extend the model inch are really substantial ones. This has given rise to a grading mechanism setting problem that has been solved in two ways. In the old Gilman lathe a single scale is used to set the adjustable member of the grading mechanism (which may be generically termed the grade bar) and it was also necessary to make a second adjustment of the pivot about which the so-called grading lever swung, to correspond to the model length. Theosetting of .a single gracing member was thus not suflicient in itself to enable the machine to grade.

The second solution of the problem appears in the machine invented by F. S. Buck, described and claimed in the United States Letters Patent No. 1,302.303, grant ed April 29, 1919. In that machine, which provided for more accurate length grading than had previously been obtainable and in which the setting of a single member is SlllllClGIlt to enable the machine to grade, irrespective of the model length, the model length is taken care of by the provision of a. special scale graduation for each length.

The present invention still further improves the art ofgrading by providing. a scale having a single set marks arranged to give the correct setting of the adjustable grade determining member solely by their relative positioning. Accord ngly, an important feature of the invention consists in the combination of the two carriages by the relative movement of which it is-desired to grade, amember, hereinafter called a grade bar, by the setting of which solely, the machine may be adjusted to grade from any model, and a single graduated scale for setting the grade bar, the graduations of the scale having the same meaning irresepctive of the length of the model. In the machine shown, the grading scale is adjustable in position to correspond to the length of the model used, and itssingle set of graduation marks preferably always have the same meaning.

These and other features of the invention, comprising various arrangements and combination of parts will be understood from the following description of a preferred embodiment thereof, selected for purposes of illustration, and shown in the accompanying drawings in which Fig. 1 is a front elevation of the essential parts of the machine;

Fig. 2 is a perspective view of the carriages;

Fig. 3 is a detail of the length grading mechanism.

The machine shown is the machine described by L. B. Whipple in his application 'Ser. No. 292,281, filed Apr. 24, 1919. Only as much of the machine as is necessary for the understanding of the present inventionis shown herein and the application referred to may be consulted for a fuller description thereof.

The main frame 10 is provided at its top with two guides 12 which extend from front to rear, which co-act with ribs 18 on the lower frame members of the slide frame.

The slide frame is formed of two bars 20 which carry the ribs 18. Mounted integrally on the bars are the verticals 22, which are joined by two bars 26 near the top and bot tom, respectively. The left hand member 22 is shown with an extension 28 carrying a roller 30 which runs in a guide 32 at the of graduation Patented am. 10, 1922. i

against distortion in the plane of the bars 26. Suitable dust guards, preferably of felt, are mounted at 36, between the slide frame and the guides 20.

The slide frame is held in its extreme forward position, when desired, for the purpose of inserting the work, for example, by a suitable latch 88, operated-by a handle 40.

Mounted on the bars 26 are the head stock frames 52, 54, and the adjustable tail stock frames 56, 58. A shaft 60 extends between the frames 52 and 54, and has gears 62, 64 near its ends. At its inner end is mounted the block driving dog 66. A stub shaft 68 is mounted in the frame 54 below the shaft. This carries a gear 70 meshing with thegear 64, and a second block driving dog 72. The frame 58 carries two corresponding block dead centers 74 of ordinary construction. The frame 52 carries a stub shaft 76, on which are mounted the gear 78 meshing with the gear 62 and the model driving dog 80. The frame 56 carries the model dead center 82 of ordinary construction. The model and blocks are driven by a sprocket 88 and appropriate gearing, not shown. The gears 62. 78, 64, 70 are all of the same size so that actuation of the sprocket 88 through a chain 144 will drive the model and lowerblock in one direction and the upper block in the oth r direction at the same speed.

The cutter carriage148 is formed with V and flat guides 150 and 152 arranged to engage a rib and a flat on the main frame,

as is usual in machines of this class. The carriage has on its upper surface a dovetail uide 154 and a flat guide 156. The model wheel carriage 158 slides on the guide 156 and has an extension 160 which runs in the guide 1 4. The width grading mechanism, compr sing the fan board 162, adjustable 'eeler 164, and slide 166 is of ordinary construction.

The cutter carriage has on its lower face a rack 168 driven by a pinion gearing 170, 72. The wheel 172 is driven by the worm 74 on a shaft 176 having a cone pulley 178 driven in the ordinary manner. The shaft 176 is raised and lowered in the ordinary manner to engage and disengage the worm 174.with the wheel 17 2. and is automatically dropped when the cutter carriage has moved to its leftmost extremity of movement (Fig. 1). This mechanism is well-known to users of the Gilman lathes and. need not be further described. The handle 182 is used to rack the cutter carriage back and forth rapidly when the gearing 172. 174 is disconnected.

The cutter carriage carries a dovetail 184 on which works a slide 186. Pivoted on this slide is a block 1.87, which can be angularly adjusted about the pivot by the bolts and segmental slots 188. The block 187 has a dovetail guide 190 in which works a grade bar'192. The block 186 is joined to the model wheel carriage by a link 194. Fixedly mounted on the cutter carriageis a dovetail guide 196 in which works a vertical bar 198 carrying two arms 200 and 202 extending toward the grade bar. The arm 200 is pivoted to the grade bar at 204 and the arm 202 has an arcuate slot 206 about 204 as center in which the lower end of the grade bar can be adjustably secured by a bolt 207. The arm 202 carries a scale 208 the reading edge of which is parallel to the bar 198 and is collinear with the center 204. The scale 208 is arranged to carry an adjustable slide 210 which carries a scale 212 at an angle of 45 with the scale 208 and with its Zero point always on the reading edge of the scale 208 whatever its adjusted position. The grade bar 192 carries a blade 214 whose reading edge is parallel to the grade bar and is collinear with the center 204.

A horizontal rack 216 is mounted .On the main frame, and a second rack 218 is mounted on the vertical bar 198. A pinion 220, inoun ed on the guide 196 connects these two racks. As the cutter carriage is driven to the left in Fig. 1 the bar 198 will be lowered vertically at the same velocity, while being carried horizontally by the carriage. If the grade bar 192 has been set in nonparallelism with the vertical bar 198 the vertical movement of the system will cause the slide 186 to move relatively toward or from the guide 196 by an amount equal to the product of the travel of the bar 196 and the tangent of the angle of adjustment of the grade bar measured from the mean position at the reading edge of the scale 208. Th s relative movement of the slide and the guide'196 will, through the link 194, move the model wheel carriage on the cutter carriage by the same amount, and thereby accomplish a length grading action on the last being cut. The relative travel of the two carriages per inch travel of the cutter carriage is equal to the offset. or departure of the grade bar from its mean position per inch measured along the mean position.

The grading mechanism may be otherwise contrived, but the form shown is strong, practical and smoothly. working, and has performed satisfactorily in practice. If the guide 196 were mounted on the model wheel carriage the offset of the grade bar per inch would equalthe relative travel of the carengaging them respectively. It is obvious that the grading action will be absolutely uniform. The fact thatthe wedge forms part of the connection between the carriages and moves transversely to their line of travel enables all lost motion in the connections to be taken up in the first 0.01 inch of cutting, so that any irregularity due to me chanical imperfections of adjustment will disappear while the stub at the end of the list is being cut, and the last itself will be graded perfectly. Any discrepancy in the relative movement of the carriages will be so small as to be negligible, as the backlash in the slide will be much less than 0.01 inch.

An important feature of the invention resides in the mechanism for setting the grade bar. The absolute amount by which any grading device is to be set depends upon the absolute size of the model used, since the grading of (for instance) inch in length per size requires different magnification ratios corresponding to different model lengths. In the ordinary Gilman'and in the Kimball Bros. & Sprague lathes the length of the grading lever is changed by moving its pivot vertically, so that the same grading scale can be used for models of different lengths. The adjustments are difiicult to make, and more or less jockeying is'always necessary when a new model is placed in the machine. All such difiiculties have been avoided by the novel setting mechanism provided by this invention.

The scale 208 is graduated in units of size measurement according to the ordinary system in use in this country, but is calibrated in units 1%,; times as large. That is, the distance between the 6 and 7 marks is inch instead of inch. The scale 212 is graduated in units of ordinary length grade, up and down, andis calibrated in units of inches. The scale 208 is so located vertically that the distance from the pivot 204 to its graduation marks are all 1. times the actual or stick lengths of the lasts corresponding to the graduations. That is, the #4 childs last is 5.271 inches long and the distance from the pivot 204 to the corresponding graduation mark is 7.906 inches. Any other multiplier .K would do, provided only that the apparatus is large enough to permit satisfactory operation. In other words, it is the angle and not the length of the wedge which effects the desired result.

Suppose it is desired to grade down 3 sizes from a 7 mens model. The scale 212 is moved up so that its zero mark coincides with the 7 mens mark-on scale 208 and the bar 192 is swung to the right so that the reading edge of the plate 214 is over the 3 mark on scale 212. Now this 8 mark is exactly vertically opposite the 4 mark on scale 208 owing to the /2 factor used in the graduation of scale 212', and the 45 angle on which it is set. Furthermore, this'8 mark is offset to the left of the 4 markby exactly 1.5' inches, or 3 sizes as measured on the scale 208, owing to the same reasons. Therefore, while the cutter carriage (and the wedge system vertically) travels the length of a #4 (i. e. 5590f the distance from the point 204 to the 4 mark of scale 208) the model wheel carriage will be relatively 1 pulled forward by an amount equal to of the distance between the 3 mark on scale 212 and the 4 mark on scale 208, or 1 inch.

In other words, the model wheel carriage will travel the length of a 7 while the cutter carriage travels the length of a #4, which is the result desired.

The 7 mens model spoken of above is a last which measures 7 on the last mea'suring stick. A 7 model will ordinarily measure more than '7 011 the stick, due to the pointed toe, but will have the #7 foot roominit and will be marked 7. The actualfstick length of the model will always be used in setting the scale 212, no attention being paid to its marked length.

Thus the single graduation scale suffices to set the grade bar for any model. Its setting to the model length is simple, and as no stress comes upon it, no bolts have to be loosened: and tightened. The system is simple,and the settingof the scale 212 can be read by puttin the model on the last measuring stick; f the vertical movement of the wedge were. governed by the ,model wheel carriage, the scale 212 would be at right angles to the scale 208 and the /2 factor would be omitted in its calibration Its adjustmentand use would be the, same.

The axis of the guide bar passes through the pivot between the block 187 and the slide 186. The automatic stop mechanism is preferably arranged to bring the pivot 204 in line with this pivot at the instant of stop. The grade bar can thenbe swung to anew adjusted position without moving the slide 184, whereas if adjustment be made when the two pivots are vertically separated, the

angular movement of the bar will cause a movement of the slide 186, and consequently of the model carriage.

The cutter carriage carries a frame in 'which are mounted the stators of'twomotors 224. The axes of the stators lie in planes parallel to the plane of the guides 12, and

passing through the axes of the block hold-" ingmeans, and are placed at an angle of about 30 with these axes respectively. The

motor rotors have small cutter heads ated with relation to the axis of the model holding means.

Havmg described my invention, What I claim as new and desire to secure by Letters Patent of the United States is r 1. In a machine of the class described, a"

carriage on the model side, a carriage on the work side and a grading mechanism for causing the carriages to move at different velocities, comprising a grade bar by the setting of which solely, the machine is adjusted to grade from any model, and a graduated scale for setting the grade bar, each graduation onthe scale indicating a certain number of sizes of the ordinary grade irrespective of the model length.

2. In a machine of the class described, a

carriage on the model side, a carriage on the -work side, and a grading mechanism for comprising a carriage on the model side, a

carriage on the work side, and a grading mechanism for causing the carriages to have systematically different movements during the last cutting, said mechanism comprising an adjustablegrade bar, and a single graduated scalefor setting the grade bar, the scale being movable into different positions to 7 effect grading from different models.

4c; A machine of the class described, comprising a carriage on the model side, a carriage on-the work side, and a grading mechanismfor causing the carriages to have systematically different movements during the last cutting, said mechanism comprising a pivoted grade bar and a single graduated scale for setting the grade bar about its pivot, the scale being movable into different positions. 'to effect grading from different models; a

5. In a machine of the class described, comprising a carriage on the model side, a carriage on the work side, and a grading mechanism for causing the carriages to have systematically different movements during the last cutting, said mechanism comprising an adjustable gradebar, and a single graduated scale for setting the grade bar, the scale being movable along the grade bar into different positions to effect grading from different models.

6. A machine of the class described, comprising a carriage on the model side, a carriage on the work side, and a grading mechanism for causing the carriages'to have systematically different movements during the last cutting, said mechanism comprising 9.

pivot, the scale being movable along the grade bar into different positions to effec grading from different models. 7

7. A machine of the class described, comprising a carriage on the model side, a carriage on the work side, and a grading mechanism for causing the carriages to have systematically different movements during the last cutting, said mechanism comprising a pivoted grade bar and a single graduated scale for setting the bar about its pivot, said scale being adjustable in correspondence with the length of model used so that its graduation interval will subtend correspond ing angles at the bar pivot.

8. A machine of the class described, com-v prising a carriage on the model side, a carriage on the ork side, and a' grading mechanism for causing the carriages to have systematically different movements .during the last cutting, said vmechanism comprising an adjustable grade bar whose offset from a mean position of the bar corresponds to the difference in travel of the carriages and a graduated scale for measuring said offset, the grading adjustment being made by the relative adjustment of the bar and the same scale graduation mark, irrespective of. the length of themodel.

9. A machine of the class described, comprising a carriage on the model side, a carriage on the work side, and a grading mechanism for causing the carriages to have systematically different movements during the last cutting, said mechanism comprising a pivoted grade bar, whose offset per inch measured in relation to a mean position is proportional to the difference in travel of the carriages, and a graduated scale graduated to show the ordinary length. grade and arranged to vary the bar ofiset corresponding to the same graduation mark in accord-. ance with V the requirements of differing model lengths.

10. A machine of the class-described, comprising a carriage on the model side, a carriage on the work side, and a grading mechanism for causing the carriages to have systematically different movements during the last cutting, said mechanism comprising a pivoted grade bar Whose offset per inch measuredin relation to a mean position is proportional to the difference in travel of the carriages, a slide arranged to move rela tively to the bar at a velocity proportional to that of a carriage and connected to a carriage to transfer the offset of the bar'into the velocity of the carriage, and a graduated scale arranged to determine the position of the grade bar for a certain grade by means of the same graduation mark irrespective of the model length. 7

11. A machine of the class described, comprising a carriage on the model side, a carriage on the work side, and a grading mechanism for causing the carriages to have systematically different movements during the last cutting, said mechanism comprising an angularly adjustable grade bar connected to one carriage, a slide moving relatively to the grade bar and connected to the other carriage, the relative movement being equal to the movement of one carriage and the offset of the grade bar per inch referred to a mean position of the bar being equal to the difference in travel of the carriages per inch travel of one of them, the offset being translated into relative movement of the carriages by the relative sliding movement, and a scale graduated in terms of the ordinary last grade, and arranged to offset its graduation points relatively to said mean position to effect the offset per inch of the grade bar corresponding to the marked grade irrespective of the length of the model.

12. A machine of the class described, comprising a carriage on the model side, a carriage on the work side, and a grading mechanism for causing the carriages to have systcmatically different movements during the last cutting, said mechanism comprising a pivotally adjustable grade bar, connected to one carriage, a slide moving relatively to the grade bar and connected to the other carriage, the relative movement being equal to the -movement of one carriage and the offset of the grade bar per inch referred to a mean position of the bar being equal to the difference in travel of the carriages per inch travel of one of them, the offset being translated into relative movement of the carriages by the relative sliding movement, and a single scale, graduated in terms of the ordinary length grade and arranged to position its graduation points at distances from the pivot point measured along the mean potional to the travel of a carriages in making the grades corresponding to the graduations and at distances offset from the mean position by amounts likewise proportional to the relative travel of the carriages while making the grades, irrespective of the model length. 7

13. A machine of the class described, comprising a carriage on the model side, a carriage on the work side, and a grading mechanism for causing the carriages'to have systematically different movements during the last cutting, said mechanism comprising a pivotally adjustable grade bar connected to one carriage, a slide moving relatively to the grade bar and connected to the other carriage, the relative movement being equal to the movement of the cutter carriage, and the offset of the grade bar per inch referred to a mean position of the bar being equal to the difference intravel of the carriages per inch travel of the cutter carriage, the offset being translated into relative movement of the carriages by the relative sliding movement, and a setting scale graduated in terms of theordinarylength grade arranged at an angle of with the mean position of the grade bar, whereby when the scale is placed upon the mean position of the grade bar at a distance from the pivot equal to the model length multiplied by the ratio of the projection of the graduation interval upon the mean position to the grade per size, the graduation points will be projected on the mean position at a distance from the pivot equally proportional to the lengths of the corresponding graded lasts and offset from the mean positlon by amounts equally proportional to the grades.

In testimony whereof I have signed my name to this specification.

STANLEY E. BOYNTON. 

